Method of repairing asphalt pavements.



JOHN T. HARROP, F GARFIELD, NEW JERSEY.

METHOD OF REPAIRING ASPHALT PAVEMENTS.

No Drawing.

To all whom it may concern.-

Be it known that I, J 01m T. HARRoP, a citizen of the United States, and residing at Garfield, in the county of Bergen and State of New Jersey, have invented certain new and useful Improvements in- Methods of Repairing Asphalt Pavements, of which the following is a specification, such as will enable those skilled in the art to which it appertains to make and use the same.

This invention relates to the art of repair- -ing or restoring what are usually known as 'asphalt pavements, or pavements in which the top or wearing surface is of varying thlckness, and composed of asphalt, or a bituminous concrete, or a composition of variable sizes of stone, gravel, and sand, or

like material, in combination with a bituminous binder, and the object of the invention is to provide a method for the purpose set out whereby a worn down, broken, depressed or otherwise injured'surface of a roadway or pavement ofthe class specified maybe restored in an eflicient manner and made flush with the original surface and as strong and durable as said original or uninjured surface of said pavement or roadway; and with this and other objects in view the invention consists of an improved method of repairing or restoring worn down places,

" depressions, breaks or holes in pavements of the class specified, no matter'how large the worn down places, depressions, breaks or, holes may be. Whenever the word depression is used alone in the following specification, it will be understood to include Worn down places, breaks, holes or other injuries of any kind to the surface of the pavement.

As is wellknown, pavements of the class specified are usually laid on a base, of concrete, broken stone, gravel and sand, or similar material and this base may-also contain a binder of bituminous material, but the character of the base, or the method of making it 'form no part of my invention.

In the practice of my invention, I preferably first thoroughly cleanse or clean the surface of the depression, hole or break in the wearing surface of the pavement, and this may be done bysweeping or brushing,

or by means of an air blast; and said depression after it has been cleaned in this manner may' also be washed, if desired. The next step in the process is to impregnate or saturate the material in which the depression ocours,'and the material-immediately surr undi g e pression, with a suita le Specification of Letters Patent.

Patented June 26, 1917.

Application filed May 23, 1916. Serial No. 99,314.

inflammable solvent such as gasolene or other similar highly inflammable petroleum prodnot which tends to cut back and soften the bituminous material in which the depression occurs. After the solvent has thoroughly impregnated the bituminous material it is ignited and allowed to burn for a period of time to thoroughly dry the base, and dry out any moisture that may be therein and also in the surrounding or contiguous pavement, and to heat the base of the surrounding or contiguous pavement to a predetermined degree and to bring the surrounding or contlguous pavement and the material in which the depression occurs to a plastic condition to receive the new or additional bitunfinous concrete or similar material used in repairing the injury to the pavement and to form a flux and with which said material readily unites.

When, the required temperature of the material in which the depression,-break, or

hole occurs, and the surrounding or contiguous material of the pavement is reached, and said material softened or made plastic to take the new material to be used in repairing the depression, the flames are extinguished by using a fireproof mat or in any other way,

and the depression is filled by first placing therein a layer of broken stone, slag, gravel or the 'likewhich is thoroughly compressed by tamping or rolling, after which bitumen heated to a temperature of approximately three hundred and twenty-five degrees is poured over the said'material, and covered with variable sizes of stone, gravel, slag,

sand or like material and then tamped or rolled down hard to form'asurface flush with the surface of the old or'original pavement. 'If the worn downpavement, depression, break or hole is of sufficient depth a layer of broken stone, gravel, sand and'the like is. first put in the depression, break or hole and covered with asphalt or other bituminous binder, after which another layer of stone, gravel, sand or the like is placed on the asphalt or bituminous binder, and this is covered with another layer of asphalt or bituminous material, and in this way there may be several layers of stone, slag, gravel,

sand or the like and asphalt or bituminous material successively placed in the depression, break or hole, and whenever a layer of stone, gravel, sand or the like is used it must be thoroughly tamped or rolled. In preparing the worn down pavement, depression, break or hole in the first up liquid asphalt, bi'tumen,

' hole, or break may stance, as herein set out, the-surrounding or contiguous asphalt, or bituminous concrete, or similar material of the original pavement may be picked or roughened in any way to insure a more ready union therewith of the asphalt, bituminous binder, or bituminous concrete used in repairing the depression, break or hole.

With my improved method it is immaterial whether the surface of the asphalt, macadam or other pavement be worn down, broken or only depressed, in the latter case, however, the cleaning out of the depression will be carried out in the manner set forth, and said depression will be saturated or impregnated with a liquid petroleum prodnot or other highly inflammable liquid which will be ignited and burned till the asphalt or other bituminous concrete or other material of the pavemen'tin the depression and adjacent thereto is heated to a plastic condition, after which the said depression may be filled in with divided stone, gravel or the like to be tamped or rolled down and onto which will be poured tar or any other suitable substance of this class which would operate as a binder, afterward be covered with sand, finely divided stone, screenings or like material which would then be tamped or rolled to form a firm hard surface.

It must also be understood that in repairing holes or breaks of any kind even where the surface of "the pavement is removed, after the hole or break has been cleaned out and heated by burning a suitable inflammable liquid therein, the said be filled in with layers of broken stone, slag, gravel, sand or the likeon which may bepoured liquid asphalt,

' break or hole may be filled water gas tar or any like substance, which will operate as a binder, and this substance will then be covered by sand,'finelv divided stone, slag or the like, after which the surface of the filling will be tamped or rolled in the usual manner, or the depression, in with a hot or cold bituminous concrete which is raked into position, after which said bituminous concrete will be tamped or rolled to form a hard and dense finish, and in the use of a bituminous or similar concrete, as herein set out, either a hot or cold mix may be employed. I

By means of my improved methodworn down, broken, depressed or otherwise injured pavements of the class specified may be quickly and easily repaired, and at an expense comparatively small, and this may be done even in the winter-time and when the places to be repaired are frozen, is no frost in the concrete or other material which substance will if there- 1,aso,894

used for filling purposes, as the burning of the highly inflammable material in the break or hole and on the surrounding pavement removes the frost therefrom and forms a flux with which said material readily unites.

I also desire it understood that wherever I have specified the use of bitumen or bituminous material as a binder that tar or similar material may be employed.-

I-Iaving fully described my invention, what I claim as new and desire to secure by Letters Patent, is

1. The method of repairing depressions in asphalt or similar pavements which consists in first saturating or impregnating the material in which the depression occurs, with a suitable inflammable solvent, which cuts back and tends to soften said material, igniting and burning said solvent to render the material in which the depression occurs,

and burning said solvent to render the material in which the depression occurs plastic, and then filling in the depression with a material containing a bituminous binder.

- 3. The method of repairing depressions in asphalt or similar pavements which'consists in first saturating or impregnating the material in which the depression occurs, with a suitable inflammable solvent, which cuts back said material, igniting and burning said solvent to render the material plastic, and then filling in the depression with successive layers of broken stone, slag, gravel or the like and a bituminous binder.

4. The method of repairing depressions in asphalt or similar pavements which consists in first thoroughly cleaning the surface of the depression, saturating or impregnating the material, in which the depression occurs, with gasolene to out back or soften the same, igniting and burning said gasolene to render the material plastic, and then filling the depression with mineral material 1 containing a bituminous binder.

In testimony that I claim the foregoing as my invention I have signed my name, in,

presence of the subscribing witnesses, this 20th day of May, 1916.

I JOHN T. HARROPQ Witnesses:

G. E. MULREANY,

H. E. THOMIPSO-N. 

